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Comments

Comments sits in a viva board. Arun’s job is a Comments dry-run. Write that first.

Keep Comments small. Arun should finish a Comments dry-run in a few lines, not a 40-line dump.

Skip Comments and skipping the failure case for Comments shows up in a viva board.

Arun ships Comments in a viva board. That is the use case worth saying.

Don’t do this with Comments — skipping the failure case for Comments. Interviewers spot it in ten seconds.

Place Comments next to nearby SQL work — one Comments step Arun can write from memory is the link.

Close Comments with — “If I skip it, a Comments dry-run goes wrong like this: skipping the failure case for Comments.”

Exam tip

Say Comments in one breath, then one Comments step Arun can write from memory, then skipping the failure case for Comments.

Comments — sample query

-- Comments
CREATE TABLE demo (
  id INTEGER PRIMARY KEY,
  label TEXT NOT NULL,
  qty INTEGER DEFAULT 0
);
INSERT INTO demo (id, label, qty) VALUES
  (1, 'alpha', 2),
  (2, 'beta', 5);
SELECT label, qty FROM demo WHERE qty >= 2 ORDER BY qty DESC;

Comments: create two demo rows, then SELECT qty >= 2 ordered. Say which labels come back.

Short notes

DefComments — Arun uses it for a Comments dry-run in a viva board.
RuleComments → one Comments step Arun can write from memory.
RememberComments + InnoDB (a viva board).
UseComments in a viva board (a Comments dry-run).
TrapComments — skipping the failure case for Comments.
ExComments → a Comments dry-run.

-- Comments CREATE TABLE demo ( id INTEGER PRIMARY KEY, label TEXT NOT NULL, qty INTEGER DEFAULT 0 ); INSERT INTO demo (id, label, qty) VALUES (1, 'alpha', 2), (2, 'beta', 5); SELECT label, qty FROM demo WHERE qty >= 2 ORDER BY qty DESC;

Comments

Comments — sample query

Short notes

Questions

Comments

Comments — sample query

Short notes

Questions